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延河流域植物光谱特征分析 被引量:15
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作者 万余庆 阎永忠 张凤丽 《国土资源遥感》 CSCD 2001年第3期15-20,共6页
介绍了延河流域主要植物的光谱特征 ,分析了形成植物光谱特征差异的主要内在原因和影响因素 ,即植物体内的叶绿素 (维生素a ,b)、胡萝卜素、氮、木质素、纤维素的含量是决定植物光谱特征的根本因素 ,植被覆盖度、太阳高度角、大气特征... 介绍了延河流域主要植物的光谱特征 ,分析了形成植物光谱特征差异的主要内在原因和影响因素 ,即植物体内的叶绿素 (维生素a ,b)、胡萝卜素、氮、木质素、纤维素的含量是决定植物光谱特征的根本因素 ,植被覆盖度、太阳高度角、大气特征、背景地物。 展开更多
关键词 植被光谱 特征分析 光谱影响因素 延河流域 太阳高度角 植被覆盖度 遥感技术
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Research of Influence Factors on Apple NIR Spectroscopy Acquisition 被引量:1
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作者 樊景超 周国民 《Agricultural Science & Technology》 CAS 2010年第9期22-25,62,共5页
[Objective] The aim was to optimize experimental conditions of Gala apple NIR(Near Infrared)spectroscopy acquisition through study on the accuracy of NIR spectroscopy information under different influence factors.[M... [Objective] The aim was to optimize experimental conditions of Gala apple NIR(Near Infrared)spectroscopy acquisition through study on the accuracy of NIR spectroscopy information under different influence factors.[Method]Gala apple was taken as the experimental material,and FieldSpec3 spectrometer(Analytical Spectral Device Company,America)was employed to acquire the NIR spectroscopy at room temperature.Then,the effects of different conditions including the environmental stray light,instrument stability,different distance,different chromatic aberration,different sites and different shelf-life on spectroscopy acquisition were investigated.[Result]The stray light had a significant effect on the visible light region of NIR spectroscopy;FieldSpec3 spectrometer had higher stability in 9 h;the measure distance of 2.5-12.5 mm could obtain good repeatability of absorbance;the effects of different chromatic aberration of the same apple on spectra was acceptable;the spectral stability of equatorial plane of the apple was better than those of the bottom and stalk;at room temperature;different shelf-life could make significant influence to NIR spectroscopy of the apple simple.[Conclusion]This study will provide reference for the researchers and analysis workers of apple NIR spectroscopy. 展开更多
关键词 APPLE Near infrared spectroscopy Influence factors
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Influence factors on activity of Ru–Zn catalysts in selective hydrogenation of benzene 被引量:1
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作者 Qi Zhang Xuhua Yan +1 位作者 Peng Zheng Zhengbao Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第3期294-300,共7页
Selective hydrogenation of benzene is an atom economic green route to produce cyclohexene. The control of Zn species is the key to the catalytic performance of Ru–Zn catalysts. The influences of ZnO crystals on selec... Selective hydrogenation of benzene is an atom economic green route to produce cyclohexene. The control of Zn species is the key to the catalytic performance of Ru–Zn catalysts. The influences of ZnO crystals on selective hydrogenation of benzene were explored. A series of Ru–Zn catalysts with different Zn contents and ZnO morphologies were prepared by changing the amount of NaOH in the co-precipitation process. The catalysts were characterized by N_2 physisorption, X-ray powder diffraction(XRD), inductively coupled plasma optical emission spectrometer(ICP-OES), scanning electron microscope(SEM), temperature-programmed reduction(H_2-TPR)and Malvern laser particle size analyzer. It is found that with increasing the amount of NaOH, the Zn content first increased then decreased, and the ZnO crystals changed from relatively thicker pyramidal-shaped crystals to slimmer needle-shaped crystals. The catalyst had the highest Zn content(22.1%) and strongest interaction between ZnO crystals and Ru particles at pH 10.6 of the solution after reduction. As a result, it had the lowest activity. The activity of Ru–Zn catalysts is affected by both the Zn content and the interaction between ZnO crystals and Ru particles. The effect of reduction time was also investigated. Prolonging the reduction time caused no significant growth of ZnO crystals but the aggregation of catalyst particles and growth of Ru nanocrystals, thus resulting in the decrease of catalytic activity. 展开更多
关键词 ZnO morphology BENZENE Selective hydrogenation CO-PRECIPITATION CYCLOHEXENE
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Study on treatment of acidic black 10B dye wastewater by chemical oxidation and adsorption of activated carbon fixed bed
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作者 LU Xiu-guo LIU Yan ZHANG Pan RAO Ting 《Journal of Environmental Science and Engineering》 2009年第7期11-13,22,共4页
Acidic black 10B dye wastewater was treated by chemical oxidation and adsorption of activated carbon fixed bed and all kinds of influential factors of removal CODcr were discussed. When the initial concentration of th... Acidic black 10B dye wastewater was treated by chemical oxidation and adsorption of activated carbon fixed bed and all kinds of influential factors of removal CODcr were discussed. When the initial concentration of the dye was 150 mg/L, CODer was 432 mg/L and chrome was 2800 times, the appropriate conditions determined by the experiment were as follows: r(NaC10)--4.84 g/L, 25 min, pH=6, height of activated carbon fixed bed was 10 cm. Under these conditions, the decolorizing rate can come up to about 100% and total removed rate of CODer reached at 89.6%. Comparison of UV-Vis adsorption spectrums before and after treatment showed that decomposition effects of chemical oxidation and adsorption of activated carbon fixed bed on acidic black 10B dye wastewater were satisfactory. 展开更多
关键词 chemical oxidation ADSORPTION acidic black 10B
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